1. Field of the Invention
The present invention relates to organic conductive polymer compositions adapted to produce touch panel input devices, transparent conductive films formed from the organic conductive polymer compositions, transparent conductors that utilize the transparent conductive films, and input devices that utilize the transparent conductors and processes for producing the input devices.
2. Description of the Related Art
Touch panels are typically disposed on front surfaces of displays such as liquid crystal displays, CRT displays, and electro-luminescence displays and are utilized as input devices. When a finger or a pen edge push a point of touch panel in an arbitrary manner, the point is detected as a coordinate position on a two-dimensional plane, and the coordinate position is outputted as an electric signal into computers or related devices.
Recently, touch panels have been widely utilized for various apparatuses, systems, and the like such as electric notebooks, cellular phones, personal handyphone systems, calculators, electric clocks, global positioning systems, bank ATM systems, vending machines, and POS systems.
Analog touch panels by the use of electric resistance have been widely utilized for various inputting devices, among others. The analog touch panels by the use of electric resistance are typically constructed from a conductive transparent film and a conductive transparent substrate that face each other, and a insulating spacer interposed between them; when a finger or a pen edge pushes a position on the touch panel in an arbitrary manner, the transparent film bends and contacts with the transparent substrate in a partial area then outputs an electrical signal.
Traditionally, polyethylene terephthalate (PET) films with a conductive layer of indium tin oxide (ITO) have been utilized widely for the transparent films. However, some problems have been present that repeating deformations of PET films bring about repeating stresses on ITO conductive layers of ceramic material, resulting in brittle fracture of ITO conductive layers and degradation of resistance; the ITO conductive layers are usually formed over entire surfaces of PET films by means of spattering process, and the patterning of the ITO conductive layers are conducted by lithography, these are considerably complicated and expensive processes; the areas on which wiring patterns being formed are to be insulated by photo resist, solder resist, insulating paste, insulating film and the like, these are also considerably complicated and expensive.
Accordingly, an electrode-bearing article has been proposed wherein a layer formed of conductive polymer and non-conductive polymer is coated additionally on the ITO conductive layer, thereby the discontinuity of ITO conductive layers is compensated and the degradation of resistance is prevented even if the ITO conductive layers undergo brittle fracture due to prolonged and repeated usages, as disclosed in Japanese Patent Application Laid-Open (JP-A) No. 11-506849. However, this proposal suffers from expensive cost for forming the layer of conductive polymer and non-conductive polymer.
Another proposal appears wherein a film containing an organic conductive polymer and p-type inorganic semiconductor is employed in place of the ITO conductive layers, as disclosed in JP-A No. 2002-93242. However, this proposal suffers from insufficient durability of the film under repeated usages for the application of touch panels.
The objects of the present invention are to provide economically organic conductive polymer compositions that can yield easily transparent conductive films with superior transparency and conductivity; transparent conductive films and transparent conductors that can be mass-produced into optional shapes with lower cost, are superior in transparency, electrical conductivity, and flexibility, and are preferable for touch panel input devices; input devices that can be mass-produced into touch panel input devices economically, hardly undergo resistance degradation even after prolonged and repeated usages, and represent remarkably improved reliability and lifetime; and effective processes for producing the input devices.